The present invention relates to an irrigation system for use with surgical retractors and devices for stabilizing a predetermined area of the body during a surgical procedure. The present invention is even more particularly directed to an irrigation system used in connection with cardiac procedures including coronary artery bypass grafting surgical procedures and valve replacement or repair procedures, and more specifically to an irrigation system for use with surgical retractors and stabilizing devices configured for use with each other for such surgical procedures.
Diseases of the cardiovascular system affect millions of people each year and are a cause of death for large numbers of people in the United States and throughout the world. A particularly prevalent form of cardiovascular disease involves a reduction in the blood supply to the heart caused by atherosclerosis (coronary artery disease) or other conditions that create a restriction in blood flow at a critical point in the cardiovascular system leading to the heart.
One technique for treating such a blockage or restriction is a surgical procedure known as a coronary artery bypass graft procedure, which is more commonly known as xe2x80x9ca heart bypassxe2x80x9d operation. The surgical correction of occluded or stenosed coronary arteries by means of bypass grafting are probably still the most common procedures performed today, particularly when multiple grafts are needed.
In the coronary artery bypass graft procedure, the surgeon either removes a portion of a vein from another part of the body for grafting or detaches one end of an artery and connects that end past the obstruction while leaving the other end attached to the arterial supply. When using a vein from another part of the body, the surgeon installs this portion at points that bypass the obstruction. In both cases, the objective is to restore normal blood flow to the heart.
In addition, when using this conventional technique, the surgeon makes a long incision down the middle of the chest, saws through the sternum and spreads the two halves of the stemum apart. The surgeon then performs several procedures necessary to connect the surgical patient to a cardiopulmonary bypass machine to continue the circulation of oxygenated blood to the rest of the body while the heart is stopped and the graft is being sewn in place. Although such a procedure is one common technique for treatment, the procedure is lengthy, traumatic, expensive and can damage the heart, the central nervous system and the blood supply of the patient.
In an effort to reduce expense, risk and trauma to the patient, physicians have also turned to minimally invasive surgical approaches to the heart, such as intercostal and endoscopic access to the surgical site. With such procedures, the heart is beating during the surgical procedure. Thus, there is no need for any form of cardiopulmonary bypass and there is no need to perform the extensive surgical procedures necessary to connect the patient to such a bypass machine.
Many attempts at performing minimally invasive bypass grafting on a beating heart, however, have been thought of as being tedious, dangerous and difficult because of the delicate nature of the surgical procedure, the lack of adequate access and visibility through a reduced surgical field, and the lack of a convenient way to adequately stabilize and reduce tissue movement at the graft site. Because these procedures are performed while the heart muscle is continuing to beat, the blood continues to flow and the heart continues to move in three dimensional movement while the surgeon is attempting to sew the graft in place. Also, the surgical procedure to install the graft requires placing a series of sutures through an extremely small vessel and onto tissue that continues to move during the procedure. It is necessary that these sutures be fully and securely placed so the graft is firmly in position and does not leak.
There is disclosed in U.S. Pat. No. 5,730,757, an access platform for the dissection of an internal mammary artery. The described access platform has first and second blades interconnected to a spreader member that laterally drives the blades apart together and support pads interconnected to the first blade. A torsional member is operably interconnected to the first blade and the spreader member and is used to vertically displace the first blade in either direction. Thus, increasing the surgeon""s working space and visual access for the dissection of the internal mammary artery. A tissue retractor interconnected to the blades is used to draw the soft tissue around the incision away from the surgeon""s work area. It is further provided that the access platform can include a port that can be used to mount a heart stabilizer instrument.
There also is described in U.S. Pat. No. 5,875,782 granted to Ferrari et al. and U.S. Pat. No. 5,894,843 granted to Benetti et al. an apparatus for stabilizing the predetermined area on a heart or other organ of a patient to enable a surgical procedure on a beating heart. The apparatus includes a bifurcated member having two elongated prongs and an elongated handle. The handle segment can be movably attached to a rib retractor so that a person is not required to hold the handle segment. In one disclosed embodiment, the apparatus further includes a device to hold the bifurcated member in a desired position against the surface of the heart so that contraction of the heart does not cause either vertical or horizontal motion at the target site during the surgical procedure.
There also is described in U.S. Pat. No. 5,836,311 granted to Borst et al. an apparatus for stabilizing the predetermined area on a heart or other organ of a patient to enable a surgical procedure on a beating heart. The apparatus includes a single legged or bifurcated member having a plurality of suction members thereon which are attached to the surface of the heart using suction pressure. The arm portion of this device can be movably attached to a rib retractor or other surgical device so a person is not required to hold the handle segment and the suction device may be locked into position against the surface of the heart
With any of these mechanical stabilization approaches, it is important to maintain a clear field of view for the surgeon to assist in the precise dissection of the surrounding tissue and placement of the sutures for the anastomosis. Additionally, if the surgical field is not clear, it is possible that the surgeon will not be able to adequately assess the viability of the blood vessel for the subsequent procedure. In the past, this has been accomplished by having the nurse squirt fluid onto the surgical field using a syringe containing normal saline. This practice requires the nurse to continually stop whatever else she is doing to locate and pick up the syringe and then squirt a small amount of fluid onto the surgical site as requested by the surgeon. Alternately, a separate device known as a blower/mister may be used to clear the surgical site. This device is a hand held device that is connected to a source of carbon dioxide or saline. Use of this device allows the nurse to direct the tip of the device to the desired area, but it is yet another instrument that is positioned in the surgical field and it requires the nurse to discontinue doing whatever else they may be doing to turn the device on, adjust the flow and move it to the desired location.
There is a continuing need however for improved devices and methods for providing the surgeon with an easier way to perform a very complicated surgical procedure while providing devices and methods that are inexpensive, safe and reliable.
The present invention features a system for aspirating a surgical field while retracting, stabilizing or manipulating a predetermined area of a body. The overall system includes a surgical retractor, a stabilization arm or apparatus and a tissue support or stabilization device with an irrigator thereon, and methods of use related thereto. Also featured is a system that supports any of a number of surgical implements, for example a diaphragm retractor, a valve retractor, a light or a suction device for use with an irrigator during a surgical procedure. The stabilization system and related devices that are featured herein are particularly advantageous for use in performing off-pump coronary artery bypass grafting procedures wherein the heart remains beating during the surgical procedure and/or valve repair or replacement procedures. One advantage of the present invention relates to the ability to maintain a clear surgical field during the surgical procedure.
The present invention further relates to an irrigation system for use with a surgical retractor system having a stabilization arm and a stabilization device. The present invention further includes a system for immobilizing tissue and providing a clear surgical field at the surgical site as well as a method of using the irrigation system with the stabilization arm and stabilization device during a surgical procedure. A preferred embodiment of the irrigation system and retractor system of the present invention includes a stabilization device having an aperture therein and that extends from the stabilization arm to a location that is adjacent to or surrounds the surgical site. Furthermore, a holder is used to position the nozzle of the irrigator adjacent to the desired location along the surgical site. A separate handle may be attached to or fabricated for use with the irrigator and/or the retractor system so that the user can manipulate the position and volume of fluid received from the irrigator as needed.
In a general aspect, the stabilization system of the present invention is preferably used for stabilizing a predetermined area of a patient. This preferred system includes a retractor for opening and spreading the chest of the patient, a stabilization device for locally stabilizing the predetermined area of tissue and a stabilization arm that functionally secures the stabilization device to the retractor. The retractor preferably includes a rail system having two arms and a rack segment. The rack segment interconnects the two arms, for selectively spacing the two arms from each other and for maintaining the two arms in a desired fixed relationship. In a preferred form of the present invention, the two arms and rack segment are configured to receive the connector of the stabilization arm at nearly any desired location thereon.
The stabilization device preferably includes a device of the type commonly known as the Cohn Cardiac Stabilizer marketed by the Genzyme Corporation of Cambridge Mass., although various horseshoe or suction type devices may also be used. The preferred form of the stabilization device is a generally square or rectangularly shaped member having a planar surface with centrally located opening therein. This opening is the area through which the surgeon performs the anastomosis or other procedure on the tissue of the beating heart. The stabilization device is preferably a two piece member so that once the anastomosis is completed, the pieces may be separated to remove the device from around the anastomosis. As described more fully below, flexible tapes are sutured through the tissue and then threaded through the stabilizing device. Once the stabilization device is positioned in the desired orientation and location in contact with the tissue, the flexible tapes are then pulled snug through the opening of the stabilization device to provide a system which minimizes the overall movement of the predetermined area of the tissue.
The stabilization arm of the present invention preferably includes an elongated handle having a first end and a connector thereon for releasably connecting the stabilization device to the distal end of the elongated handle. This connection allows the stabilization device to be pivotally and slidably moved to a desired position into contact with the predetermined area of the tissue of the patient while minimizing the interference of the stabilization device and stabilization arm with the field of view at the surgical site. The stabilization arm also includes a mounting mechanism or sled member which is preferably slidable along the retractor for removably securing the stabilization arm to at least one of the rails on the retractor arms and/or the rack segment of the retractor.
According to a preferred form of the present invention, the arms of the retractor are configured with a front edge and a step in the top surface thereof to form an elongated rail surface along substantially the entire length thereof. The step is preferably spaced apart a predetermined and consistent distance from the front edge and is also located on the interconnecting or rack segment of the retractor. Also, the stabilization arm preferably includes a mounting mechanism or sled member which is configured to removably engage the front edge and the step at any desired location on one or more of the arms or the rack segment of the retractor. The mounting mechanism includes a lever for selectively engaging the step and front edge on the arm or rack segment of the retractor so the mounting mechanism is removably and slidably secured to the arms or the rack segment.
In another aspect of the present invention, there is featured a surgical retractor including two arms, a rack segment and a plurality of sternal blades with at least one blade extending downwardly from each arm. Each blade includes an upper section adjacent to the bottom surface of the arm and a lower section extending distally of the arm. A slot on the bottom surface of the arms includes a tapered surface adjacent to the front edge thereof to facilitate the placement of the blades on the arms. A lip surface is also located adjacent to the slots on the bottom surface of the arms to securely retain the blades on the bottom surface of the arms during the procedure while still allowing the blades to be easily removable for initial positioning and subsequent sterilization following the procedure.
Each of these features enables the user to determine the optimum position for the stabilization arm and stabilization device while ensuring that the surgeon""s view of the operative area is not unnecessarily obstructed. Additionally, these features allow the present invention to be used in many different medical procedures because of the versatility of system set up and orientation of the components of this invention.
In another preferred aspect of the present invention, the irrigation system includes a source of sterile fluid such as an IV bag of normal saline that is hung remotely from the surgical site. A flexible fluid delivery line extends from the bag, along the preferably rigid stabilization arm to a nozzle which is preferably removably attached to the handle portion of the stabilization arm on the retractor system. The fluid delivery line is preferably releasably and adjustably attached to the stabilization arm by a plurality of adjustable clamps to ensure that the delivery line is maintained away from the surgical field. Additionally, the nozzle is preferably adjustable to nearly any orientation with respect to the stabilization arm and stabilization device such that as the stabilization device is oriented to provide the optimum contact with the tissue of the patient, the nozzle may also be adjusted to provide the optimum orientation with respect to the surgical site to provide the desired flow of fluid to the surgical site without unnecessarily obstructing the surgical site or interfering with the surgical procedure.
The coronary arteries of the typical patient are about 1-2 mm in diameter, and the pumping heart can move these arteries over distances of several millimeters during each heartbeat. Therefore, movement of even 1 or 2 millimeters can result in a displacement of the grafting site that can substantially interfere with effective anastomosis, it is therefore desirable to restrain movement of the artery at the surgical site. Additionally, it is very important to keep the surgical site as clear as possible so that the surgeon may perform the anastomosis or other delicate procedure without interference from blood or other debris. Therefore, the irrigator provides an easily positionable nozzle and a flow control member to allow the location and flow of fluid to be adjusted depending on the needs and/or desires of the surgeon during the particular surgery. Additionally, the connection of the nozzle to the stabilization arm is preferably through a frictional member such that when the nozzle is aimed at the desired location, it will stay in that orientation until it is readjusted.
In another form of the present invention, the irrigation system may be connected to a regulated source of carbon dioxide to allow the user to direct a stream of carbon dioxide to the surgical site. As with the irrigation system described above, the flexible delivery line is connected to the stabilization arm by at least one and preferably two clamp members to ensure that the delivery line is maintained adjacent to the stabilization arm and does not interfere with the surgical site.
Other aspects and embodiments of the invention are more fully discussed below.